Legionella longbeachae detected in an industrial cooling tower linked to a legionellosis outbreak, New Zealand, 2015; possible waterborne transmission?

Autor: Thornley CN; MidCentral Public Health Services, MidCentral District Health Board,Palmerston North,New Zealand., Harte DJ; Institute of Environmental Science and Research Ltd,Porirua,New Zealand., Weir RP; MidCentral Public Health Services, MidCentral District Health Board,Palmerston North,New Zealand., Allen LJ; MidCentral Public Health Services, MidCentral District Health Board,Palmerston North,New Zealand., Knightbridge KJ; MidCentral Public Health Services, MidCentral District Health Board,Palmerston North,New Zealand., Wood PRT; MidCentral Public Health Services, MidCentral District Health Board,Palmerston North,New Zealand.
Jazyk: angličtina
Zdroj: Epidemiology and infection [Epidemiol Infect] 2017 Aug; Vol. 145 (11), pp. 2382-2389. Date of Electronic Publication: 2017 Jun 19.
DOI: 10.1017/S0950268817001170
Abstrakt: A legionellosis outbreak at an industrial site was investigated to identify and control the source. Cases were identified from disease notifications, workplace illness records, and from clinicians. Cases were interviewed for symptoms and risk factors and tested for legionellosis. Implicated environmental sources were sampled and tested for legionella. We identified six cases with Legionnaires' disease and seven with Pontiac fever; all had been exposed to aerosols from the cooling towers on the site. Nine cases had evidence of infection with either Legionella pneumophila serogroup (sg) 1 or Legionella longbeachae sg1; these organisms were also isolated from the cooling towers. There was 100% DNA sequence homology between cooling tower and clinical isolates of L. pneumophila sg1 using sequence-based typing analysis; no clinical L. longbeachae isolates were available to compare with environmental isolates. Routine monitoring of the towers prior to the outbreak failed to detect any legionella. Data from this outbreak indicate that L. pneumophila sg1 transmission occurred from the cooling towers; in addition, L. longbeachae transmission was suggested but remains unproven. L. longbeachae detection in cooling towers has not been previously reported in association with legionellosis outbreaks. Waterborne transmission should not be discounted in investigations for the source of L. longbeachae infection.
Databáze: MEDLINE